1. Field of the Invention
The invention relates to image sensor devices, and in particular, relates to light transmitting regions of the image sensor images and method for manufacturing the same.
2. Description of the Related Art
Recently, image sensing devices such as solid state image sensing devices are used in a wide range of optoelectronic devices including, for example, digital cameras, cellular phones, toys, and the likes. Conventional image sensing devices include photo sensors such as charge coupled device (CCD) photo sensors and complementary metal oxide semiconductor (CMOS) photo sensors.
In the art of solid state imaging devices, microlenses are typically provided to improve image sensitivity. In addition, a diaphragm is typically provided within the solid state imaging device as a light path filter of the microlenses; thereby regulating the amount of light that passes through the microlenses and toward the photo sensors therein.
The diaphragm is typically defined over a top surface of the microlenses by forming a light-shielding pattern over the top surface of the microlenses by photolithography techniques. Since the microlenses are typically provided with a curved surface, photolithography techniques performed to the portion of a light-shielding layer formed over the curved surface of the microlenses may result in uneven exposure and non-uniformity during patterning thereof. Moreover, the use of photolithography techniques also has disadvantages such as increasing fabrication costs and time.
In Taiwan Patent application No. 097119486, the inventors of the invention utilize energy-induced swelling sacrificial elements to pattern a metal layer to form a light-shielding pattern or an electromagnetic interference pattern. However, the interaction between the metal pattern (serving as the light-shielding pattern/electromagnetic interference pattern) and a lens upper surface is weak, such that the metal pattern easily peels or cracks from the lens upper surface due to subsequent cleaning steps.
Accordingly, a novel method is called for manufacturing the light transmitting region of the image sensor device; such that the product yield is free of the influence of the metal fragments come from the electromagnetic interference pattern.